Why Do Breastfed Babies Need Vitamin D?

why do breastfed babies need vitamin d image

Estimated reading time: 5 minutes

Breast milk is the best food you can give your baby! It is specifically designed for your baby’s nutrition, development, and immunity. Given the superpowers of breast milk, it might surprise you when your pediatrician recommends you give your newborn baby a vitamin D supplement. You might think, “Wait a second! I thought breast milk was practically perfect? Why do Breastfed Babies Need vitamin D?” Let’s shine some light on the reasons behind this recommendation and how you can ensure your baby gets the right amount.

Why Do We All Need Vitamin D?

Vitamin D is crucial for everyone, but it’s especially important for babies, as it helps build strong bones and teeth. It plays a significant role in the absorption of calcium and phosphorus, two minerals that your baby needs for healthy bone development. It’s also essential for immune function, muscle strength, and brain development.

Risks of Low Vitamin D in Babies and Children

  1. Rickets: The most well-known risk of vitamin D deficiency in infants and children is rickets, a condition that causes bones to soften and weaken, leading to skeletal deformities, delayed growth, and in severe cases, dental problems.
  2. Bone Health: Low vitamin D levels can affect bone density and lead to future issues like osteoporosis or bone fractures.
  3. Immune Function: Vitamin D is essential for the immune system. Deficiency may increase the risk of infections and autoimmune diseases.
  4. Respiratory Problems: Some studies suggest that low vitamin D levels in early life may be linked to a higher risk of respiratory issues like asthma and wheezing disorders.

Some researchers are also beginning to correlate vitamin D deficiency and the following (3):

  • Colon, Breast, and Prostate Cancers
  • Hypertension
  • Diabetes
  • Multiple sclerosis, rheumatoid arthritis, and other autoimmune conditions

Why Do Breastfed Babies Not Have Enough Vitamin D?

Limited Vitamin D in Breast Milk: While breast milk is the best source of nutrition for infants, it doesn’t contain enough vitamin D to meet your baby’s daily needs. This isn’t about the quality of your breast milk; it’s just the nature of vitamin D.

Limited Sun Exposure: Our bodies produce vitamin D when exposed to sunlight. However, newborns and infants don’t typically spend much time in direct sunlight (which is also not recommended due to their sensitive skin).

How Do I Supplement My Breastfed Baby With Vitamin D?

Vitamin D Drops

The American Academy of Pediatrics recommends that both breastfed and partially-breastfed babies should supplement with 400IU of vitamin D each day, beginning when baby is a few days old. This supplementation should continue until baby either switches to a Vitamin-D fortified formula or fortified cow’s milk, sometime after baby’s first birthday.

You can buy a liquid vitamin D supplement for your baby at any drug store. After a few months, your pediatrician might recommend you switch to a liquid multivitamin that includes vitamin D.

Mom’s Vitamin D

Recent studies explore the idea of supplementing moms with lots of vitamin D to see if enough vitamin D will pass on to their breastfed babies. These studies are still relatively new and debated, and the AAP still recommends you supplement your breastfed baby.

That said, you should still be mindful your own vitamin D levels, mama. Another study reported that 81% of women of childbearing age have insufficient levels of vitamin D. Yikes! You can get more vitamin D through some safe time in the sun, eating certain foods, or taking a supplement.

Vitamin D Through Food

Once your baby starts eating solid foods, you can start enriching his vitamin D intake through food. Some examples of foods with vitamin D include the following:

  • Some fish (such as tuna or salmon)
  • Eggs
  • Vitamin D-fortified products like cow’s milk (for children 12 months and older), yogurt, cereals, and some juices.

Administering the Drops

  1. Use the Dropper: Most Vitamin D drops come with a dropper or a syringe. Draw up the recommended amount (usually one drop or 0.5 ml, depending on the concentration).
  2. Direct Administration: Gently open your baby’s mouth and place the dropper at their lips. Release the drop onto their tongue. It’s a small amount, so it won’t be overwhelming for your baby.
  3. Give It On The Breast: If direct administration is challenging, you can also put the drop on your nipple before breastfeeding or on a pacifier.

Giving Your Breastfed Baby Vitamin D: Make It A Habit

Put those vitamin D drops in a specific spot, so it will become a simple habit to give to your baby. For example, you can put the drops by the changing table and give them at each morning diaper change. Or you can put them in a kitchen cabinet and give them after you eat breakfast. You do you!

It’s still true—breast milk is the best option for your baby. Vitamin D is a nutrient none of us typically get from food alone, so we need to supplement it for our sweet little ones. Your baby needs those strong bones! Above all, remember, you are keeping a little human being alive and healthy. You are amazing!

Kopa Birth’s online childbirth classes allow you to prepare for a natural childbirth in the comfort of your own home, 24/7. Enroll today in our free online childbirth class to learn more about preparing for natural childbirth. 


  1. CAPPA: Childbirth & Postpartum Professional Association. (2016). Lactation Educator Manual (Ninth Edition).
  2. Centers for Disease Control and Prevention (2020, October 8). Breastfeeding: Vitamin D. Retrieved December 5, 2020, from https://www.cdc.gov/breastfeeding/breastfeeding-special-circumstances/diet-and-micronutrients/vitamin-d.html
  3. La Leche League International. Vitamin D, Your Baby, and You. Retrieved December 5, 2020 from https://www.llli.org/breastfeeding-info/vitamin-d/
  4. Shute, N. (2011, June 6). A Baby’s Skin Is No Match For The Sun. NPR. Retrieved December 5, 2020 from https://www.npr.org/sections/health-shots/2011/06/06/137010355/a-babys-skin-is-no-match-for-the-sun
  5. McNeill, A.M., & Wesner, E. (2018, May 14). Sun Protection and Vitamin D. Skin Cancer Foundation. Retrieved December 5, 2020 from https://www.skincancer.org/blog/sun-protection-and-vitamin-d/

Here are some other birth articles and stories we know you’ll love.

Meet Katie Griffin

I’m a registered nurse, Lamaze certified childbirth educator, and the mother of 7. I help women realize their dream of a natural, intimate, and empowering hospital birth.

You may also like

Breast milk is the best food you can give your baby! It is specifically designed for your baby’s nutrition, development, and immunity. Given the superpowers of breast milk, it might